22121520 has 40 divisors (see below), whose sum is σ = 68577456. Its totient is φ = 5899008.

The previous prime is 22121513. The next prime is 22121521. The reversal of 22121520 is 2512122.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×22121520² = 978723294220800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 22121520.

It is not an unprimeable number, because it can be changed into a prime (22121521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45847 + ... + 46326.

Almost surely, 2^22121520 is an apocalyptic number.

22121520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22121520 is an abundant number, since it is smaller than the sum of its proper divisors (46455936).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22121520 is a wasteful number, since it uses less digits than its factorization.

22121520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92189 (or 92183 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 22121520 is about 4703.3519961831. The cubic root of 22121520 is about 280.7189009391.

Adding to 22121520 its reverse (2512122), we get a palindrome (24633642).

The spelling of 22121520 in words is "twenty-two million, one hundred twenty-one thousand, five hundred twenty".